"It is a huge, huge effort," said the first-five, who scored 23 of Wales's 28 points at Twickenham stadium, a record points haul for a Welshman against England.

"For us to come here to England's home ground at the World Cup - no one gave us a hope, we had a million and one injuries."

"This is the best day rugby-wise of probably my whole career."

Each time England looked to stretch away, with leads of up to 10 points, the hosts' indiscipline and Biggar's unerring boot reeled them back in.

His captain Sam Warburton said the win was all the more remarkable given their long injury list, which only lengthened in the heavyweight Pool A clash.

"It just shows the spirit and the strength of the squad, that even though we have lost those top-quality players we can still come to a place like Twickenham, one of the hardest places to come in the world, and get an away victory."

England head coach Stuart Lancaster was left to rue his team's regular infringements and a crucial decision in the final minutes to kick for the corner and go for the win rather than attempt a penalty kick from a difficult angle to secure a draw.

"In hindsight it was wrong," he said of the decision.

"Players have to make the decision on the field. It was a huge moment, but overall, irrespective, the game should have been done and dusted.

"We played well for long periods, so to come away with a loss is gutting. It is still all to play for, but this has made it hard work."

The win puts Wales top of Pool A with nine points, four points ahead of England and in prime position to make the knockout stages.

Both teams still need to face Australia, but that match-up now looks like a must-win game for England.